1. Field of the Invention
The present invention relates to a data input apparatus for inputting coordinate data for moving or rotating an image displayed on the display screen of a computer system.
2. Description of the Related Art
FIG. 5 is a plan view of a data input apparatus of the related art utilizing so-called a track ball.
A spherical manipulator 1 called a track ball is supported to freely rotate in the three-dimensional directions in order to drive an X encoder 2 and a Y encoder 3 in these directions.
The X encoder 2 comprises a roller 2a which rotates around the axis extending in the Y direction and a disc 2b which rotates together- with the roller 2a. At the external circumference of the disc 2b, cutout sections are formed. These cutout portions and the section where the cutout section is not formed are alternately formed in the circumference direction with a constant pitch At the external circumference section of the disc 2b, a photocoupler 2c is provided opposing thereto. The photocoupler 2c is provided with a light emitting element and a light receiving element opposed to each other and the external circumference of the disc 2b is provided between the light emitting element and light receiving element. When the roller 2a and disc 2b rotate, a pulse output of the frequency depending on the rotating velocity of the disc 2b can be obtained.
In the same manner, the Y encoder comprises a roller 3a rotating around the axis extending in the X direction, a disc 3b rotating together with this roller 3a, and a photocoupler 3c provided opposed to the external circumference of the disc 3b. At the external circumference of the disc 3b, the cutout portions and the section where the cutout section is not formed are formed alternately in the circumference direction in the constant pitch. Thereby, a pulse output in the frequency depending on the rotating velocity of the roller 3a and disc 3b can be obtained from the photocoupler 3c.
An ordinary input operation occurring when the data input apparatus explained above is connected to a computer will be explained below.
When the spherical manipulator 1 is rotated in the X direction, the roller 2a and disc 2b of the X encoder 2 rotate and thereby a pulse output can be obtained from the photocoupler 2c and it is then converted to the coordinate data. When this coordinate data is input to the computer, a cursor or character and object on the display image moves in the X direction, for example, on the display screen connected to the computer. Moreover, when the manipulator 1 is rotated in the Y direction, the roller 3a and disc 3b of the Y encoder 3 rotate, a pulse output from the photocoupler is converted to the coordinate data, and is then input. Thereby the cursor, etc. moves in the Y direction on the image explained above.
Moreover, when the manipulator 1 is rotated, for example, in the .alpha. direction having an angle for both X and Y axes, both roller 2a and roller 3a are rotated, the pulses from the photocoupler 2c and photocoupler 3c are converted into the coordinate data and thereby the cursor is moved in the .alpha. direction on the display image.
Moreover, it is also possible to input the data of rotating mode as the coordinate data by rotating the manipulator 1, for example, while the predetermined key on the keyboard is depressed. When the manipulator 1 is rotated in the X direction, for example, while depressing the key explained above and thereby the pulse output can be obtained from the photocoupler 2c of the X encoder, this pulse output is converted to the rotating data on the coordinate and is then input to the computer. As a result, a character or object, for example, displayed on the display image is rotated around the Y axis (.theta.y direction). In the same manner, when the manipulator 1 is rotated in the Y direction while depressing the key, the character explained above rotates, for example, around the X axis (.theta.x direction) on the display image.
Namely, the character, etc. on the display image rotates in the same direction as the manipulator 1. Therefore, when the manipulator 1 is rotated in the .alpha. direction, the character, etc. rotates around the axis orthogonal to the .alpha. direction.
As explained above, in the data input apparatus comprising the spherical manipulator 1, X encoder 2 and Y encoder 3, the coordinate data of the moving direction, amount of movement and moving velocity in the two-dimension of the X-Y coordinates can be input and moreover the rotating data around the Y axis and the rotating data around the X axis can also be input in the input mode of the rotating coordinate. However, the input coordinate data is limited only to that explained above and it is a disadvantage of the related art that it is impossible to execute the following input.
(1) When inputting the rotating data on the coordinate, the rotating data around the Z axis orthogonal to the X and Y axes cannot be input. Namely, as explained above, when the manipulator 1 is rotated in the X direction or in the Y direction in the rotating mode where the predetermined key is depressed, it is possible to input the data to rotate the character in the same direction as the manipulator 1 on the display image. However, even when the manipulator 1 is rotated in the .theta.z direction (rotation around the X axis) in FIG. 5, the rotating data around the Z axis cannot be input. Namely, if the manipulator 1 rotates in the .theta.z direction, the X encoder 2 and Y encoder 3 rotate due to the elements around the X axis and Y axis of the manipulator 1 during this rotation and the character tries to rotate only around the X axis and Y axis depending on such output pulse. PA0 (2) In the input apparatus shown in FIG. 5, the moving data in the Z axis direction cannot be input. Therefore, it is impossible to input the data for moving, for example, the character and object appearing on the display image in different directions such as X axis and Y axis directions. PA0 (3) As explained above, in the data input apparatus of the related art, it is possible to input the coordinate data with reference to the X-Y coordinates forming the orthogonal coordinates on the horizontal plane where this data input apparatus is installed, but it is impossible to input the data in the coordinates with reference to the Y-Z plane other than the X-Y plane and moreover to input the data to the coordinates on the plane inclining against the X-Y plane. PA0 (4) In the data input apparatus of the two-dimensional input type as shown in FIG. 5, when the X encoder 2 is rotated depending on the operation of the manipulator 1, an object M on the display image (refer to the coordinates in the image of FIG. 2) moves in the X axis direction and when the Y encoder 3 is rotated, the object M on the image moves in the Y axis direction. In this case, regarding the X axis direction, the rotating direction of the manipulator 1 visually matches the moving direction of the object M on the display image but regarding the Y axis direction, although the manipulator 1 is actually moving in the Y axis direction, the moving direction of the object M moves in the vertical direction of the image, namely in the Z axis direction and therefore visual matching of the movement cannot be obtained. Therefore, when inputting the three-dimensional data in the X-Y-Z coordinates by improving the data input apparatus of this type, it is assumed that correspondence between operation and rotation in the direction of axis or around the axis may be confused.